Fruit and veg is cheap if you buy in season local stuff, or frozen or canned which all still counts. What pushes the price up is buying out of season imported fancy stuff like asparagus or purple sprouting broccoli.
But it's stuff like this that is just not true any more. It's based on how shopping used to be twenty, thirty years ago.
In supermarkets, there is no "cheap in season local stuff". The cheap stuff is the out of season air-freighted imported stuff. Try buying a local apple in Tesco. The cheap ones are all imported. Asparagus is cheap as chips nowadays - it's air-freighted and can be grown hydroponically. Kiwi fruits used to be thought of as a delicacy - they're cheaper these days than British Cox's apples (and air-freighted from NZ). (Coxes or any British apples are £££ compared to imported Granny Smiths). Grapes air-freighted from Galicia or the Philippines all year round - always cheap on offers. Cheap overseas bananas. Cheap strawberries from Israel, air-freighted.
If you haven't got a local farm shop, it's going to cost you a lot more to buy "in-season local produce" than buying air-freighted stuff. This is the paradox about food buying that loads of people haven't really caught up with. Buy processed, imported and pre-prepared - cheap food. Try to buy fresh local fruit and veg in a supermarket in a city? You are paying through the nose.
At least £30-40 of my weekly shop goes on fruit and veg - and that's just on the bog-standard pears, apples, bananas, plums, kiwis, broccoli, greens, cabbage, carrots, onions, lettuce, cucumber, tomatoes, green beans, celery and so on. They are NOT cheap! We are hardly "living it up" on purple sprouting broccoli every night
(though actually things like imported asparagus and mange tout are nearly always cheap and on special offers like the 2 for £2.50 ones).
Ditto canned or frozen veg - yes that's a lot cheaper; but actually it isn't nearly as good for you as well as tasting disgusting and things like baked beans, canned veg were only actually included in the government "5-a-day" advice because it was thought people would never meet the requirements if they were told to eat the amount of fresh veg that was required.... The original recommendations were at least 8 portions a day fresh fruit and veg. Tinned mixed veg is cheap as chips but it's not doing much for you health-wise compared to fresh veg.